Memory storage capability in integrated circuits is usually provided by memory elements, or memory cells, organized in arrays. The total storage capacity can be further divided in smaller sized arrays, or physical blocks, depending on the memory technology and/or on the programming and erasing mechanisms.
For example, NOR-type flash memories often have two or more physical memory blocks. These physical blocks are physically separated from each other and may be operated selectively. As an example, it is possible to access and read a physical block while the data in a different block is being changed. In order to ensure independent operation each physical block must be provided with appropriate decoding circuitry to ensure electrical insulation between the physical blocks. Both separation and local decoding circuitry space lead to an increased overall cost.